1/*
2 * video.c - ACPI Video Driver
3 *
4 * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5 * Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
6 * Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21 */
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/init.h>
26#include <linux/types.h>
27#include <linux/list.h>
28#include <linux/mutex.h>
29#include <linux/input.h>
30#include <linux/backlight.h>
31#include <linux/thermal.h>
32#include <linux/sort.h>
33#include <linux/pci.h>
34#include <linux/pci_ids.h>
35#include <linux/slab.h>
36#include <linux/dmi.h>
37#include <linux/suspend.h>
38#include <linux/acpi.h>
39#include <acpi/video.h>
40#include <linux/uaccess.h>
41
42#define PREFIX "ACPI: "
43
44#define ACPI_VIDEO_BUS_NAME "Video Bus"
45#define ACPI_VIDEO_DEVICE_NAME "Video Device"
46
47#define MAX_NAME_LEN 20
48
49#define _COMPONENT ACPI_VIDEO_COMPONENT
50ACPI_MODULE_NAME("video");
51
52MODULE_AUTHOR("Bruno Ducrot");
53MODULE_DESCRIPTION("ACPI Video Driver");
54MODULE_LICENSE("GPL");
55
56static bool brightness_switch_enabled = true;
57module_param(brightness_switch_enabled, bool, 0644);
58
59/*
60 * By default, we don't allow duplicate ACPI video bus devices
61 * under the same VGA controller
62 */
63static bool allow_duplicates;
64module_param(allow_duplicates, bool, 0644);
65
66static int disable_backlight_sysfs_if = -1;
67module_param(disable_backlight_sysfs_if, int, 0444);
68
69#define REPORT_OUTPUT_KEY_EVENTS 0x01
70#define REPORT_BRIGHTNESS_KEY_EVENTS 0x02
71static int report_key_events = -1;
72module_param(report_key_events, int, 0644);
73MODULE_PARM_DESC(report_key_events,
74 "0: none, 1: output changes, 2: brightness changes, 3: all");
75
76/*
77 * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
78 * assumed even if not actually set.
79 */
80static bool device_id_scheme = false;
81module_param(device_id_scheme, bool, 0444);
82
83static int only_lcd = -1;
84module_param(only_lcd, int, 0444);
85
86static int register_count;
87static DEFINE_MUTEX(register_count_mutex);
88static DEFINE_MUTEX(video_list_lock);
89static LIST_HEAD(video_bus_head);
90static int acpi_video_bus_add(struct acpi_device *device);
91static int acpi_video_bus_remove(struct acpi_device *device);
92static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
93void acpi_video_detect_exit(void);
94
95/*
96 * Indices in the _BCL method response: the first two items are special,
97 * the rest are all supported levels.
98 *
99 * See page 575 of the ACPI spec 3.0
100 */
101enum acpi_video_level_idx {
102 ACPI_VIDEO_AC_LEVEL, /* level when machine has full power */
103 ACPI_VIDEO_BATTERY_LEVEL, /* level when machine is on batteries */
104 ACPI_VIDEO_FIRST_LEVEL, /* actual supported levels begin here */
105};
106
107static const struct acpi_device_id video_device_ids[] = {
108 {ACPI_VIDEO_HID, 0},
109 {"", 0},
110};
111MODULE_DEVICE_TABLE(acpi, video_device_ids);
112
113static struct acpi_driver acpi_video_bus = {
114 .name = "video",
115 .class = ACPI_VIDEO_CLASS,
116 .ids = video_device_ids,
117 .ops = {
118 .add = acpi_video_bus_add,
119 .remove = acpi_video_bus_remove,
120 .notify = acpi_video_bus_notify,
121 },
122};
123
124struct acpi_video_bus_flags {
125 u8 multihead:1; /* can switch video heads */
126 u8 rom:1; /* can retrieve a video rom */
127 u8 post:1; /* can configure the head to */
128 u8 reserved:5;
129};
130
131struct acpi_video_bus_cap {
132 u8 _DOS:1; /* Enable/Disable output switching */
133 u8 _DOD:1; /* Enumerate all devices attached to display adapter */
134 u8 _ROM:1; /* Get ROM Data */
135 u8 _GPD:1; /* Get POST Device */
136 u8 _SPD:1; /* Set POST Device */
137 u8 _VPO:1; /* Video POST Options */
138 u8 reserved:2;
139};
140
141struct acpi_video_device_attrib {
142 u32 display_index:4; /* A zero-based instance of the Display */
143 u32 display_port_attachment:4; /* This field differentiates the display type */
144 u32 display_type:4; /* Describe the specific type in use */
145 u32 vendor_specific:4; /* Chipset Vendor Specific */
146 u32 bios_can_detect:1; /* BIOS can detect the device */
147 u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
148 the VGA device. */
149 u32 pipe_id:3; /* For VGA multiple-head devices. */
150 u32 reserved:10; /* Must be 0 */
151
152 /*
153 * The device ID might not actually follow the scheme described by this
154 * struct acpi_video_device_attrib. If it does, then this bit
155 * device_id_scheme is set; otherwise, other fields should be ignored.
156 *
157 * (but also see the global flag device_id_scheme)
158 */
159 u32 device_id_scheme:1;
160};
161
162struct acpi_video_enumerated_device {
163 union {
164 u32 int_val;
165 struct acpi_video_device_attrib attrib;
166 } value;
167 struct acpi_video_device *bind_info;
168};
169
170struct acpi_video_bus {
171 struct acpi_device *device;
172 bool backlight_registered;
173 u8 dos_setting;
174 struct acpi_video_enumerated_device *attached_array;
175 u8 attached_count;
176 u8 child_count;
177 struct acpi_video_bus_cap cap;
178 struct acpi_video_bus_flags flags;
179 struct list_head video_device_list;
180 struct mutex device_list_lock; /* protects video_device_list */
181 struct list_head entry;
182 struct input_dev *input;
183 char phys[32]; /* for input device */
184 struct notifier_block pm_nb;
185};
186
187struct acpi_video_device_flags {
188 u8 crt:1;
189 u8 lcd:1;
190 u8 tvout:1;
191 u8 dvi:1;
192 u8 bios:1;
193 u8 unknown:1;
194 u8 notify:1;
195 u8 reserved:1;
196};
197
198struct acpi_video_device_cap {
199 u8 _ADR:1; /* Return the unique ID */
200 u8 _BCL:1; /* Query list of brightness control levels supported */
201 u8 _BCM:1; /* Set the brightness level */
202 u8 _BQC:1; /* Get current brightness level */
203 u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
204 u8 _DDC:1; /* Return the EDID for this device */
205};
206
207struct acpi_video_device {
208 unsigned long device_id;
209 struct acpi_video_device_flags flags;
210 struct acpi_video_device_cap cap;
211 struct list_head entry;
212 struct delayed_work switch_brightness_work;
213 int switch_brightness_event;
214 struct acpi_video_bus *video;
215 struct acpi_device *dev;
216 struct acpi_video_device_brightness *brightness;
217 struct backlight_device *backlight;
218 struct thermal_cooling_device *cooling_dev;
219};
220
221static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
222static void acpi_video_device_rebind(struct acpi_video_bus *video);
223static void acpi_video_device_bind(struct acpi_video_bus *video,
224 struct acpi_video_device *device);
225static int acpi_video_device_enumerate(struct acpi_video_bus *video);
226static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
227 int level);
228static int acpi_video_device_lcd_get_level_current(
229 struct acpi_video_device *device,
230 unsigned long long *level, bool raw);
231static int acpi_video_get_next_level(struct acpi_video_device *device,
232 u32 level_current, u32 event);
233static void acpi_video_switch_brightness(struct work_struct *work);
234
235/* backlight device sysfs support */
236static int acpi_video_get_brightness(struct backlight_device *bd)
237{
238 unsigned long long cur_level;
239 int i;
240 struct acpi_video_device *vd = bl_get_data(bd);
241
242 if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
243 return -EINVAL;
244 for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
245 if (vd->brightness->levels[i] == cur_level)
246 return i - ACPI_VIDEO_FIRST_LEVEL;
247 }
248 return 0;
249}
250
251static int acpi_video_set_brightness(struct backlight_device *bd)
252{
253 int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
254 struct acpi_video_device *vd = bl_get_data(bd);
255
256 cancel_delayed_work(&vd->switch_brightness_work);
257 return acpi_video_device_lcd_set_level(vd,
258 vd->brightness->levels[request_level]);
259}
260
261static const struct backlight_ops acpi_backlight_ops = {
262 .get_brightness = acpi_video_get_brightness,
263 .update_status = acpi_video_set_brightness,
264};
265
266/* thermal cooling device callbacks */
267static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
268 unsigned long *state)
269{
270 struct acpi_device *device = cooling_dev->devdata;
271 struct acpi_video_device *video = acpi_driver_data(device);
272
273 *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
274 return 0;
275}
276
277static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
278 unsigned long *state)
279{
280 struct acpi_device *device = cooling_dev->devdata;
281 struct acpi_video_device *video = acpi_driver_data(device);
282 unsigned long long level;
283 int offset;
284
285 if (acpi_video_device_lcd_get_level_current(video, &level, false))
286 return -EINVAL;
287 for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
288 offset++)
289 if (level == video->brightness->levels[offset]) {
290 *state = video->brightness->count - offset - 1;
291 return 0;
292 }
293
294 return -EINVAL;
295}
296
297static int
298video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
299{
300 struct acpi_device *device = cooling_dev->devdata;
301 struct acpi_video_device *video = acpi_driver_data(device);
302 int level;
303
304 if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
305 return -EINVAL;
306
307 state = video->brightness->count - state;
308 level = video->brightness->levels[state - 1];
309 return acpi_video_device_lcd_set_level(video, level);
310}
311
312static const struct thermal_cooling_device_ops video_cooling_ops = {
313 .get_max_state = video_get_max_state,
314 .get_cur_state = video_get_cur_state,
315 .set_cur_state = video_set_cur_state,
316};
317
318/*
319 * --------------------------------------------------------------------------
320 * Video Management
321 * --------------------------------------------------------------------------
322 */
323
324static int
325acpi_video_device_lcd_query_levels(acpi_handle handle,
326 union acpi_object **levels)
327{
328 int status;
329 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
330 union acpi_object *obj;
331
332
333 *levels = NULL;
334
335 status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
336 if (!ACPI_SUCCESS(status))
337 return status;
338 obj = (union acpi_object *)buffer.pointer;
339 if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
340 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
341 status = -EFAULT;
342 goto err;
343 }
344
345 *levels = obj;
346
347 return 0;
348
349err:
350 kfree(buffer.pointer);
351
352 return status;
353}
354
355static int
356acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
357{
358 int status;
359 int state;
360
361 status = acpi_execute_simple_method(device->dev->handle,
362 "_BCM", level);
363 if (ACPI_FAILURE(status)) {
364 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
365 return -EIO;
366 }
367
368 device->brightness->curr = level;
369 for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
370 state++)
371 if (level == device->brightness->levels[state]) {
372 if (device->backlight)
373 device->backlight->props.brightness =
374 state - ACPI_VIDEO_FIRST_LEVEL;
375 return 0;
376 }
377
378 ACPI_ERROR((AE_INFO, "Current brightness invalid"));
379 return -EINVAL;
380}
381
382/*
383 * For some buggy _BQC methods, we need to add a constant value to
384 * the _BQC return value to get the actual current brightness level
385 */
386
387static int bqc_offset_aml_bug_workaround;
388static int video_set_bqc_offset(const struct dmi_system_id *d)
389{
390 bqc_offset_aml_bug_workaround = 9;
391 return 0;
392}
393
394static int video_disable_backlight_sysfs_if(
395 const struct dmi_system_id *d)
396{
397 if (disable_backlight_sysfs_if == -1)
398 disable_backlight_sysfs_if = 1;
399 return 0;
400}
401
402static int video_set_device_id_scheme(const struct dmi_system_id *d)
403{
404 device_id_scheme = true;
405 return 0;
406}
407
408static int video_enable_only_lcd(const struct dmi_system_id *d)
409{
410 only_lcd = true;
411 return 0;
412}
413
414static int video_set_report_key_events(const struct dmi_system_id *id)
415{
416 if (report_key_events == -1)
417 report_key_events = (uintptr_t)id->driver_data;
418 return 0;
419}
420
421static const struct dmi_system_id video_dmi_table[] = {
422 /*
423 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
424 */
425 {
426 .callback = video_set_bqc_offset,
427 .ident = "Acer Aspire 5720",
428 .matches = {
429 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
430 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
431 },
432 },
433 {
434 .callback = video_set_bqc_offset,
435 .ident = "Acer Aspire 5710Z",
436 .matches = {
437 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
438 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
439 },
440 },
441 {
442 .callback = video_set_bqc_offset,
443 .ident = "eMachines E510",
444 .matches = {
445 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
446 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
447 },
448 },
449 {
450 .callback = video_set_bqc_offset,
451 .ident = "Acer Aspire 5315",
452 .matches = {
453 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
454 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
455 },
456 },
457 {
458 .callback = video_set_bqc_offset,
459 .ident = "Acer Aspire 7720",
460 .matches = {
461 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
462 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
463 },
464 },
465
466 /*
467 * Some machines have a broken acpi-video interface for brightness
468 * control, but still need an acpi_video_device_lcd_set_level() call
469 * on resume to turn the backlight power on. We Enable backlight
470 * control on these systems, but do not register a backlight sysfs
471 * as brightness control does not work.
472 */
473 {
474 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
475 .callback = video_disable_backlight_sysfs_if,
476 .ident = "Toshiba Portege R700",
477 .matches = {
478 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
479 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
480 },
481 },
482 {
483 /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
484 .callback = video_disable_backlight_sysfs_if,
485 .ident = "Toshiba Portege R830",
486 .matches = {
487 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
488 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
489 },
490 },
491 {
492 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
493 .callback = video_disable_backlight_sysfs_if,
494 .ident = "Toshiba Satellite R830",
495 .matches = {
496 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
497 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
498 },
499 },
500 /*
501 * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
502 * but the IDs actually follow the Device ID Scheme.
503 */
504 {
505 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
506 .callback = video_set_device_id_scheme,
507 .ident = "ESPRIMO Mobile M9410",
508 .matches = {
509 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
510 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
511 },
512 },
513 /*
514 * Some machines have multiple video output devices, but only the one
515 * that is the type of LCD can do the backlight control so we should not
516 * register backlight interface for other video output devices.
517 */
518 {
519 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
520 .callback = video_enable_only_lcd,
521 .ident = "ESPRIMO Mobile M9410",
522 .matches = {
523 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
524 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
525 },
526 },
527 /*
528 * Some machines report wrong key events on the acpi-bus, suppress
529 * key event reporting on these. Note this is only intended to work
530 * around events which are plain wrong. In some cases we get double
531 * events, in this case acpi-video is considered the canonical source
532 * and the events from the other source should be filtered. E.g.
533 * by calling acpi_video_handles_brightness_key_presses() from the
534 * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
535 */
536 {
537 .callback = video_set_report_key_events,
538 .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
539 .ident = "Dell Vostro V131",
540 .matches = {
541 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
542 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
543 },
544 },
545 {}
546};
547
548static unsigned long long
549acpi_video_bqc_value_to_level(struct acpi_video_device *device,
550 unsigned long long bqc_value)
551{
552 unsigned long long level;
553
554 if (device->brightness->flags._BQC_use_index) {
555 /*
556 * _BQC returns an index that doesn't account for the first 2
557 * items with special meaning (see enum acpi_video_level_idx),
558 * so we need to compensate for that by offsetting ourselves
559 */
560 if (device->brightness->flags._BCL_reversed)
561 bqc_value = device->brightness->count -
562 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
563
564 level = device->brightness->levels[bqc_value +
565 ACPI_VIDEO_FIRST_LEVEL];
566 } else {
567 level = bqc_value;
568 }
569
570 level += bqc_offset_aml_bug_workaround;
571
572 return level;
573}
574
575static int
576acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
577 unsigned long long *level, bool raw)
578{
579 acpi_status status = AE_OK;
580 int i;
581
582 if (device->cap._BQC || device->cap._BCQ) {
583 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
584
585 status = acpi_evaluate_integer(device->dev->handle, buf,
586 NULL, level);
587 if (ACPI_SUCCESS(status)) {
588 if (raw) {
589 /*
590 * Caller has indicated he wants the raw
591 * value returned by _BQC, so don't furtherly
592 * mess with the value.
593 */
594 return 0;
595 }
596
597 *level = acpi_video_bqc_value_to_level(device, *level);
598
599 for (i = ACPI_VIDEO_FIRST_LEVEL;
600 i < device->brightness->count; i++)
601 if (device->brightness->levels[i] == *level) {
602 device->brightness->curr = *level;
603 return 0;
604 }
605 /*
606 * BQC returned an invalid level.
607 * Stop using it.
608 */
609 ACPI_WARNING((AE_INFO,
610 "%s returned an invalid level",
611 buf));
612 device->cap._BQC = device->cap._BCQ = 0;
613 } else {
614 /*
615 * Fixme:
616 * should we return an error or ignore this failure?
617 * dev->brightness->curr is a cached value which stores
618 * the correct current backlight level in most cases.
619 * ACPI video backlight still works w/ buggy _BQC.
620 * http://bugzilla.kernel.org/show_bug.cgi?id=12233
621 */
622 ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
623 device->cap._BQC = device->cap._BCQ = 0;
624 }
625 }
626
627 *level = device->brightness->curr;
628 return 0;
629}
630
631static int
632acpi_video_device_EDID(struct acpi_video_device *device,
633 union acpi_object **edid, ssize_t length)
634{
635 int status;
636 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
637 union acpi_object *obj;
638 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
639 struct acpi_object_list args = { 1, &arg0 };
640
641
642 *edid = NULL;
643
644 if (!device)
645 return -ENODEV;
646 if (length == 128)
647 arg0.integer.value = 1;
648 else if (length == 256)
649 arg0.integer.value = 2;
650 else
651 return -EINVAL;
652
653 status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
654 if (ACPI_FAILURE(status))
655 return -ENODEV;
656
657 obj = buffer.pointer;
658
659 if (obj && obj->type == ACPI_TYPE_BUFFER)
660 *edid = obj;
661 else {
662 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
663 status = -EFAULT;
664 kfree(obj);
665 }
666
667 return status;
668}
669
670/* bus */
671
672/*
673 * Arg:
674 * video : video bus device pointer
675 * bios_flag :
676 * 0. The system BIOS should NOT automatically switch(toggle)
677 * the active display output.
678 * 1. The system BIOS should automatically switch (toggle) the
679 * active display output. No switch event.
680 * 2. The _DGS value should be locked.
681 * 3. The system BIOS should not automatically switch (toggle) the
682 * active display output, but instead generate the display switch
683 * event notify code.
684 * lcd_flag :
685 * 0. The system BIOS should automatically control the brightness level
686 * of the LCD when the power changes from AC to DC
687 * 1. The system BIOS should NOT automatically control the brightness
688 * level of the LCD when the power changes from AC to DC.
689 * Return Value:
690 * -EINVAL wrong arg.
691 */
692
693static int
694acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
695{
696 acpi_status status;
697
698 if (!video->cap._DOS)
699 return 0;
700
701 if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
702 return -EINVAL;
703 video->dos_setting = (lcd_flag << 2) | bios_flag;
704 status = acpi_execute_simple_method(video->device->handle, "_DOS",
705 (lcd_flag << 2) | bios_flag);
706 if (ACPI_FAILURE(status))
707 return -EIO;
708
709 return 0;
710}
711
712/*
713 * Simple comparison function used to sort backlight levels.
714 */
715
716static int
717acpi_video_cmp_level(const void *a, const void *b)
718{
719 return *(int *)a - *(int *)b;
720}
721
722/*
723 * Decides if _BQC/_BCQ for this system is usable
724 *
725 * We do this by changing the level first and then read out the current
726 * brightness level, if the value does not match, find out if it is using
727 * index. If not, clear the _BQC/_BCQ capability.
728 */
729static int acpi_video_bqc_quirk(struct acpi_video_device *device,
730 int max_level, int current_level)
731{
732 struct acpi_video_device_brightness *br = device->brightness;
733 int result;
734 unsigned long long level;
735 int test_level;
736
737 /* don't mess with existing known broken systems */
738 if (bqc_offset_aml_bug_workaround)
739 return 0;
740
741 /*
742 * Some systems always report current brightness level as maximum
743 * through _BQC, we need to test another value for them. However,
744 * there is a subtlety:
745 *
746 * If the _BCL package ordering is descending, the first level
747 * (br->levels[2]) is likely to be 0, and if the number of levels
748 * matches the number of steps, we might confuse a returned level to
749 * mean the index.
750 *
751 * For example:
752 *
753 * current_level = max_level = 100
754 * test_level = 0
755 * returned level = 100
756 *
757 * In this case 100 means the level, not the index, and _BCM failed.
758 * Still, if the _BCL package ordering is descending, the index of
759 * level 0 is also 100, so we assume _BQC is indexed, when it's not.
760 *
761 * This causes all _BQC calls to return bogus values causing weird
762 * behavior from the user's perspective. For example:
763 *
764 * xbacklight -set 10; xbacklight -set 20;
765 *
766 * would flash to 90% and then slowly down to the desired level (20).
767 *
768 * The solution is simple; test anything other than the first level
769 * (e.g. 1).
770 */
771 test_level = current_level == max_level
772 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
773 : max_level;
774
775 result = acpi_video_device_lcd_set_level(device, test_level);
776 if (result)
777 return result;
778
779 result = acpi_video_device_lcd_get_level_current(device, &level, true);
780 if (result)
781 return result;
782
783 if (level != test_level) {
784 /* buggy _BQC found, need to find out if it uses index */
785 if (level < br->count) {
786 if (br->flags._BCL_reversed)
787 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
788 if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
789 br->flags._BQC_use_index = 1;
790 }
791
792 if (!br->flags._BQC_use_index)
793 device->cap._BQC = device->cap._BCQ = 0;
794 }
795
796 return 0;
797}
798
799int acpi_video_get_levels(struct acpi_device *device,
800 struct acpi_video_device_brightness **dev_br,
801 int *pmax_level)
802{
803 union acpi_object *obj = NULL;
804 int i, max_level = 0, count = 0, level_ac_battery = 0;
805 union acpi_object *o;
806 struct acpi_video_device_brightness *br = NULL;
807 int result = 0;
808 u32 value;
809
810 if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
811 &obj))) {
812 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
813 "LCD brightness level\n"));
814 result = -ENODEV;
815 goto out;
816 }
817
818 if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
819 result = -EINVAL;
820 goto out;
821 }
822
823 br = kzalloc(sizeof(*br), GFP_KERNEL);
824 if (!br) {
825 printk(KERN_ERR "can't allocate memory\n");
826 result = -ENOMEM;
827 goto out;
828 }
829
830 /*
831 * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
832 * in order to account for buggy BIOS which don't export the first two
833 * special levels (see below)
834 */
835 br->levels = kmalloc_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
836 sizeof(*br->levels),
837 GFP_KERNEL);
838 if (!br->levels) {
839 result = -ENOMEM;
840 goto out_free;
841 }
842
843 for (i = 0; i < obj->package.count; i++) {
844 o = (union acpi_object *)&obj->package.elements[i];
845 if (o->type != ACPI_TYPE_INTEGER) {
846 printk(KERN_ERR PREFIX "Invalid data\n");
847 continue;
848 }
849 value = (u32) o->integer.value;
850 /* Skip duplicate entries */
851 if (count > ACPI_VIDEO_FIRST_LEVEL
852 && br->levels[count - 1] == value)
853 continue;
854
855 br->levels[count] = value;
856
857 if (br->levels[count] > max_level)
858 max_level = br->levels[count];
859 count++;
860 }
861
862 /*
863 * some buggy BIOS don't export the levels
864 * when machine is on AC/Battery in _BCL package.
865 * In this case, the first two elements in _BCL packages
866 * are also supported brightness levels that OS should take care of.
867 */
868 for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
869 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
870 level_ac_battery++;
871 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
872 level_ac_battery++;
873 }
874
875 if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
876 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
877 br->flags._BCL_no_ac_battery_levels = 1;
878 for (i = (count - 1 + level_ac_battery);
879 i >= ACPI_VIDEO_FIRST_LEVEL; i--)
880 br->levels[i] = br->levels[i - level_ac_battery];
881 count += level_ac_battery;
882 } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
883 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
884
885 /* Check if the _BCL package is in a reversed order */
886 if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
887 br->flags._BCL_reversed = 1;
888 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
889 count - ACPI_VIDEO_FIRST_LEVEL,
890 sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
891 acpi_video_cmp_level, NULL);
892 } else if (max_level != br->levels[count - 1])
893 ACPI_ERROR((AE_INFO,
894 "Found unordered _BCL package"));
895
896 br->count = count;
897 *dev_br = br;
898 if (pmax_level)
899 *pmax_level = max_level;
900
901out:
902 kfree(obj);
903 return result;
904out_free:
905 kfree(br);
906 goto out;
907}
908EXPORT_SYMBOL(acpi_video_get_levels);
909
910/*
911 * Arg:
912 * device : video output device (LCD, CRT, ..)
913 *
914 * Return Value:
915 * Maximum brightness level
916 *
917 * Allocate and initialize device->brightness.
918 */
919
920static int
921acpi_video_init_brightness(struct acpi_video_device *device)
922{
923 int i, max_level = 0;
924 unsigned long long level, level_old;
925 struct acpi_video_device_brightness *br = NULL;
926 int result = -EINVAL;
927
928 result = acpi_video_get_levels(device->dev, &br, &max_level);
929 if (result)
930 return result;
931 device->brightness = br;
932
933 /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
934 br->curr = level = max_level;
935
936 if (!device->cap._BQC)
937 goto set_level;
938
939 result = acpi_video_device_lcd_get_level_current(device,
940 &level_old, true);
941 if (result)
942 goto out_free_levels;
943
944 result = acpi_video_bqc_quirk(device, max_level, level_old);
945 if (result)
946 goto out_free_levels;
947 /*
948 * cap._BQC may get cleared due to _BQC is found to be broken
949 * in acpi_video_bqc_quirk, so check again here.
950 */
951 if (!device->cap._BQC)
952 goto set_level;
953
954 level = acpi_video_bqc_value_to_level(device, level_old);
955 /*
956 * On some buggy laptops, _BQC returns an uninitialized
957 * value when invoked for the first time, i.e.
958 * level_old is invalid (no matter whether it's a level
959 * or an index). Set the backlight to max_level in this case.
960 */
961 for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
962 if (level == br->levels[i])
963 break;
964 if (i == br->count || !level)
965 level = max_level;
966
967set_level:
968 result = acpi_video_device_lcd_set_level(device, level);
969 if (result)
970 goto out_free_levels;
971
972 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
973 "found %d brightness levels\n",
974 br->count - ACPI_VIDEO_FIRST_LEVEL));
975 return 0;
976
977out_free_levels:
978 kfree(br->levels);
979 kfree(br);
980 device->brightness = NULL;
981 return result;
982}
983
984/*
985 * Arg:
986 * device : video output device (LCD, CRT, ..)
987 *
988 * Return Value:
989 * None
990 *
991 * Find out all required AML methods defined under the output
992 * device.
993 */
994
995static void acpi_video_device_find_cap(struct acpi_video_device *device)
996{
997 if (acpi_has_method(device->dev->handle, "_ADR"))
998 device->cap._ADR = 1;
999 if (acpi_has_method(device->dev->handle, "_BCL"))
1000 device->cap._BCL = 1;
1001 if (acpi_has_method(device->dev->handle, "_BCM"))
1002 device->cap._BCM = 1;
1003 if (acpi_has_method(device->dev->handle, "_BQC")) {
1004 device->cap._BQC = 1;
1005 } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1006 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1007 device->cap._BCQ = 1;
1008 }
1009
1010 if (acpi_has_method(device->dev->handle, "_DDC"))
1011 device->cap._DDC = 1;
1012}
1013
1014/*
1015 * Arg:
1016 * device : video output device (VGA)
1017 *
1018 * Return Value:
1019 * None
1020 *
1021 * Find out all required AML methods defined under the video bus device.
1022 */
1023
1024static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1025{
1026 if (acpi_has_method(video->device->handle, "_DOS"))
1027 video->cap._DOS = 1;
1028 if (acpi_has_method(video->device->handle, "_DOD"))
1029 video->cap._DOD = 1;
1030 if (acpi_has_method(video->device->handle, "_ROM"))
1031 video->cap._ROM = 1;
1032 if (acpi_has_method(video->device->handle, "_GPD"))
1033 video->cap._GPD = 1;
1034 if (acpi_has_method(video->device->handle, "_SPD"))
1035 video->cap._SPD = 1;
1036 if (acpi_has_method(video->device->handle, "_VPO"))
1037 video->cap._VPO = 1;
1038}
1039
1040/*
1041 * Check whether the video bus device has required AML method to
1042 * support the desired features
1043 */
1044
1045static int acpi_video_bus_check(struct acpi_video_bus *video)
1046{
1047 acpi_status status = -ENOENT;
1048 struct pci_dev *dev;
1049
1050 if (!video)
1051 return -EINVAL;
1052
1053 dev = acpi_get_pci_dev(video->device->handle);
1054 if (!dev)
1055 return -ENODEV;
1056 pci_dev_put(dev);
1057
1058 /*
1059 * Since there is no HID, CID and so on for VGA driver, we have
1060 * to check well known required nodes.
1061 */
1062
1063 /* Does this device support video switching? */
1064 if (video->cap._DOS || video->cap._DOD) {
1065 if (!video->cap._DOS) {
1066 printk(KERN_WARNING FW_BUG
1067 "ACPI(%s) defines _DOD but not _DOS\n",
1068 acpi_device_bid(video->device));
1069 }
1070 video->flags.multihead = 1;
1071 status = 0;
1072 }
1073
1074 /* Does this device support retrieving a video ROM? */
1075 if (video->cap._ROM) {
1076 video->flags.rom = 1;
1077 status = 0;
1078 }
1079
1080 /* Does this device support configuring which video device to POST? */
1081 if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1082 video->flags.post = 1;
1083 status = 0;
1084 }
1085
1086 return status;
1087}
1088
1089/*
1090 * --------------------------------------------------------------------------
1091 * Driver Interface
1092 * --------------------------------------------------------------------------
1093 */
1094
1095/* device interface */
1096static struct acpi_video_device_attrib *
1097acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1098{
1099 struct acpi_video_enumerated_device *ids;
1100 int i;
1101
1102 for (i = 0; i < video->attached_count; i++) {
1103 ids = &video->attached_array[i];
1104 if ((ids->value.int_val & 0xffff) == device_id)
1105 return &ids->value.attrib;
1106 }
1107
1108 return NULL;
1109}
1110
1111static int
1112acpi_video_get_device_type(struct acpi_video_bus *video,
1113 unsigned long device_id)
1114{
1115 struct acpi_video_enumerated_device *ids;
1116 int i;
1117
1118 for (i = 0; i < video->attached_count; i++) {
1119 ids = &video->attached_array[i];
1120 if ((ids->value.int_val & 0xffff) == device_id)
1121 return ids->value.int_val;
1122 }
1123
1124 return 0;
1125}
1126
1127static int
1128acpi_video_bus_get_one_device(struct acpi_device *device,
1129 struct acpi_video_bus *video)
1130{
1131 unsigned long long device_id;
1132 int status, device_type;
1133 struct acpi_video_device *data;
1134 struct acpi_video_device_attrib *attribute;
1135
1136 status =
1137 acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1138 /* Some device omits _ADR, we skip them instead of fail */
1139 if (ACPI_FAILURE(status))
1140 return 0;
1141
1142 data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1143 if (!data)
1144 return -ENOMEM;
1145
1146 strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1147 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1148 device->driver_data = data;
1149
1150 data->device_id = device_id;
1151 data->video = video;
1152 data->dev = device;
1153 INIT_DELAYED_WORK(&data->switch_brightness_work,
1154 acpi_video_switch_brightness);
1155
1156 attribute = acpi_video_get_device_attr(video, device_id);
1157
1158 if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1159 switch (attribute->display_type) {
1160 case ACPI_VIDEO_DISPLAY_CRT:
1161 data->flags.crt = 1;
1162 break;
1163 case ACPI_VIDEO_DISPLAY_TV:
1164 data->flags.tvout = 1;
1165 break;
1166 case ACPI_VIDEO_DISPLAY_DVI:
1167 data->flags.dvi = 1;
1168 break;
1169 case ACPI_VIDEO_DISPLAY_LCD:
1170 data->flags.lcd = 1;
1171 break;
1172 default:
1173 data->flags.unknown = 1;
1174 break;
1175 }
1176 if (attribute->bios_can_detect)
1177 data->flags.bios = 1;
1178 } else {
1179 /* Check for legacy IDs */
1180 device_type = acpi_video_get_device_type(video, device_id);
1181 /* Ignore bits 16 and 18-20 */
1182 switch (device_type & 0xffe2ffff) {
1183 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1184 data->flags.crt = 1;
1185 break;
1186 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1187 data->flags.lcd = 1;
1188 break;
1189 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1190 data->flags.tvout = 1;
1191 break;
1192 default:
1193 data->flags.unknown = 1;
1194 }
1195 }
1196
1197 acpi_video_device_bind(video, data);
1198 acpi_video_device_find_cap(data);
1199
1200 mutex_lock(&video->device_list_lock);
1201 list_add_tail(&data->entry, &video->video_device_list);
1202 mutex_unlock(&video->device_list_lock);
1203
1204 return status;
1205}
1206
1207/*
1208 * Arg:
1209 * video : video bus device
1210 *
1211 * Return:
1212 * none
1213 *
1214 * Enumerate the video device list of the video bus,
1215 * bind the ids with the corresponding video devices
1216 * under the video bus.
1217 */
1218
1219static void acpi_video_device_rebind(struct acpi_video_bus *video)
1220{
1221 struct acpi_video_device *dev;
1222
1223 mutex_lock(&video->device_list_lock);
1224
1225 list_for_each_entry(dev, &video->video_device_list, entry)
1226 acpi_video_device_bind(video, dev);
1227
1228 mutex_unlock(&video->device_list_lock);
1229}
1230
1231/*
1232 * Arg:
1233 * video : video bus device
1234 * device : video output device under the video
1235 * bus
1236 *
1237 * Return:
1238 * none
1239 *
1240 * Bind the ids with the corresponding video devices
1241 * under the video bus.
1242 */
1243
1244static void
1245acpi_video_device_bind(struct acpi_video_bus *video,
1246 struct acpi_video_device *device)
1247{
1248 struct acpi_video_enumerated_device *ids;
1249 int i;
1250
1251 for (i = 0; i < video->attached_count; i++) {
1252 ids = &video->attached_array[i];
1253 if (device->device_id == (ids->value.int_val & 0xffff)) {
1254 ids->bind_info = device;
1255 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1256 }
1257 }
1258}
1259
1260static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1261{
1262 struct acpi_video_bus *video = device->video;
1263 int i;
1264
1265 /*
1266 * If we have a broken _DOD or we have more than 8 output devices
1267 * under the graphics controller node that we can't proper deal with
1268 * in the operation region code currently, no need to test.
1269 */
1270 if (!video->attached_count || video->child_count > 8)
1271 return true;
1272
1273 for (i = 0; i < video->attached_count; i++) {
1274 if ((video->attached_array[i].value.int_val & 0xfff) ==
1275 (device->device_id & 0xfff))
1276 return true;
1277 }
1278
1279 return false;
1280}
1281
1282/*
1283 * Arg:
1284 * video : video bus device
1285 *
1286 * Return:
1287 * < 0 : error
1288 *
1289 * Call _DOD to enumerate all devices attached to display adapter
1290 *
1291 */
1292
1293static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1294{
1295 int status;
1296 int count;
1297 int i;
1298 struct acpi_video_enumerated_device *active_list;
1299 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1300 union acpi_object *dod = NULL;
1301 union acpi_object *obj;
1302
1303 if (!video->cap._DOD)
1304 return AE_NOT_EXIST;
1305
1306 status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1307 if (!ACPI_SUCCESS(status)) {
1308 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1309 return status;
1310 }
1311
1312 dod = buffer.pointer;
1313 if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1314 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1315 status = -EFAULT;
1316 goto out;
1317 }
1318
1319 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1320 dod->package.count));
1321
1322 active_list = kcalloc(1 + dod->package.count,
1323 sizeof(struct acpi_video_enumerated_device),
1324 GFP_KERNEL);
1325 if (!active_list) {
1326 status = -ENOMEM;
1327 goto out;
1328 }
1329
1330 count = 0;
1331 for (i = 0; i < dod->package.count; i++) {
1332 obj = &dod->package.elements[i];
1333
1334 if (obj->type != ACPI_TYPE_INTEGER) {
1335 printk(KERN_ERR PREFIX
1336 "Invalid _DOD data in element %d\n", i);
1337 continue;
1338 }
1339
1340 active_list[count].value.int_val = obj->integer.value;
1341 active_list[count].bind_info = NULL;
1342 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1343 (int)obj->integer.value));
1344 count++;
1345 }
1346
1347 kfree(video->attached_array);
1348
1349 video->attached_array = active_list;
1350 video->attached_count = count;
1351
1352out:
1353 kfree(buffer.pointer);
1354 return status;
1355}
1356
1357static int
1358acpi_video_get_next_level(struct acpi_video_device *device,
1359 u32 level_current, u32 event)
1360{
1361 int min, max, min_above, max_below, i, l, delta = 255;
1362 max = max_below = 0;
1363 min = min_above = 255;
1364 /* Find closest level to level_current */
1365 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1366 l = device->brightness->levels[i];
1367 if (abs(l - level_current) < abs(delta)) {
1368 delta = l - level_current;
1369 if (!delta)
1370 break;
1371 }
1372 }
1373 /* Ajust level_current to closest available level */
1374 level_current += delta;
1375 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1376 l = device->brightness->levels[i];
1377 if (l < min)
1378 min = l;
1379 if (l > max)
1380 max = l;
1381 if (l < min_above && l > level_current)
1382 min_above = l;
1383 if (l > max_below && l < level_current)
1384 max_below = l;
1385 }
1386
1387 switch (event) {
1388 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1389 return (level_current < max) ? min_above : min;
1390 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1391 return (level_current < max) ? min_above : max;
1392 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1393 return (level_current > min) ? max_below : min;
1394 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1395 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1396 return 0;
1397 default:
1398 return level_current;
1399 }
1400}
1401
1402static void
1403acpi_video_switch_brightness(struct work_struct *work)
1404{
1405 struct acpi_video_device *device = container_of(to_delayed_work(work),
1406 struct acpi_video_device, switch_brightness_work);
1407 unsigned long long level_current, level_next;
1408 int event = device->switch_brightness_event;
1409 int result = -EINVAL;
1410
1411 /* no warning message if acpi_backlight=vendor or a quirk is used */
1412 if (!device->backlight)
1413 return;
1414
1415 if (!device->brightness)
1416 goto out;
1417
1418 result = acpi_video_device_lcd_get_level_current(device,
1419 &level_current,
1420 false);
1421 if (result)
1422 goto out;
1423
1424 level_next = acpi_video_get_next_level(device, level_current, event);
1425
1426 result = acpi_video_device_lcd_set_level(device, level_next);
1427
1428 if (!result)
1429 backlight_force_update(device->backlight,
1430 BACKLIGHT_UPDATE_HOTKEY);
1431
1432out:
1433 if (result)
1434 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1435}
1436
1437int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1438 void **edid)
1439{
1440 struct acpi_video_bus *video;
1441 struct acpi_video_device *video_device;
1442 union acpi_object *buffer = NULL;
1443 acpi_status status;
1444 int i, length;
1445
1446 if (!device || !acpi_driver_data(device))
1447 return -EINVAL;
1448
1449 video = acpi_driver_data(device);
1450
1451 for (i = 0; i < video->attached_count; i++) {
1452 video_device = video->attached_array[i].bind_info;
1453 length = 256;
1454
1455 if (!video_device)
1456 continue;
1457
1458 if (!video_device->cap._DDC)
1459 continue;
1460
1461 if (type) {
1462 switch (type) {
1463 case ACPI_VIDEO_DISPLAY_CRT:
1464 if (!video_device->flags.crt)
1465 continue;
1466 break;
1467 case ACPI_VIDEO_DISPLAY_TV:
1468 if (!video_device->flags.tvout)
1469 continue;
1470 break;
1471 case ACPI_VIDEO_DISPLAY_DVI:
1472 if (!video_device->flags.dvi)
1473 continue;
1474 break;
1475 case ACPI_VIDEO_DISPLAY_LCD:
1476 if (!video_device->flags.lcd)
1477 continue;
1478 break;
1479 }
1480 } else if (video_device->device_id != device_id) {
1481 continue;
1482 }
1483
1484 status = acpi_video_device_EDID(video_device, &buffer, length);
1485
1486 if (ACPI_FAILURE(status) || !buffer ||
1487 buffer->type != ACPI_TYPE_BUFFER) {
1488 length = 128;
1489 status = acpi_video_device_EDID(video_device, &buffer,
1490 length);
1491 if (ACPI_FAILURE(status) || !buffer ||
1492 buffer->type != ACPI_TYPE_BUFFER) {
1493 continue;
1494 }
1495 }
1496
1497 *edid = buffer->buffer.pointer;
1498 return length;
1499 }
1500
1501 return -ENODEV;
1502}
1503EXPORT_SYMBOL(acpi_video_get_edid);
1504
1505static int
1506acpi_video_bus_get_devices(struct acpi_video_bus *video,
1507 struct acpi_device *device)
1508{
1509 int status = 0;
1510 struct acpi_device *dev;
1511
1512 /*
1513 * There are systems where video module known to work fine regardless
1514 * of broken _DOD and ignoring returned value here doesn't cause
1515 * any issues later.
1516 */
1517 acpi_video_device_enumerate(video);
1518
1519 list_for_each_entry(dev, &device->children, node) {
1520
1521 status = acpi_video_bus_get_one_device(dev, video);
1522 if (status) {
1523 dev_err(&dev->dev, "Can't attach device\n");
1524 break;
1525 }
1526 video->child_count++;
1527 }
1528 return status;
1529}
1530
1531/* acpi_video interface */
1532
1533/*
1534 * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1535 * preform any automatic brightness change on receiving a notification.
1536 */
1537static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1538{
1539 return acpi_video_bus_DOS(video, 0,
1540 acpi_osi_is_win8() ? 1 : 0);
1541}
1542
1543static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1544{
1545 return acpi_video_bus_DOS(video, 0,
1546 acpi_osi_is_win8() ? 0 : 1);
1547}
1548
1549static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1550{
1551 struct acpi_video_bus *video = acpi_driver_data(device);
1552 struct input_dev *input;
1553 int keycode = 0;
1554
1555 if (!video || !video->input)
1556 return;
1557
1558 input = video->input;
1559
1560 switch (event) {
1561 case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
1562 * most likely via hotkey. */
1563 keycode = KEY_SWITCHVIDEOMODE;
1564 break;
1565
1566 case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
1567 * connector. */
1568 acpi_video_device_enumerate(video);
1569 acpi_video_device_rebind(video);
1570 keycode = KEY_SWITCHVIDEOMODE;
1571 break;
1572
1573 case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
1574 keycode = KEY_SWITCHVIDEOMODE;
1575 break;
1576 case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
1577 keycode = KEY_VIDEO_NEXT;
1578 break;
1579 case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
1580 keycode = KEY_VIDEO_PREV;
1581 break;
1582
1583 default:
1584 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1585 "Unsupported event [0x%x]\n", event));
1586 break;
1587 }
1588
1589 if (acpi_notifier_call_chain(device, event, 0))
1590 /* Something vetoed the keypress. */
1591 keycode = 0;
1592
1593 if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1594 input_report_key(input, keycode, 1);
1595 input_sync(input);
1596 input_report_key(input, keycode, 0);
1597 input_sync(input);
1598 }
1599
1600 return;
1601}
1602
1603static void brightness_switch_event(struct acpi_video_device *video_device,
1604 u32 event)
1605{
1606 if (!brightness_switch_enabled)
1607 return;
1608
1609 video_device->switch_brightness_event = event;
1610 schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1611}
1612
1613static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1614{
1615 struct acpi_video_device *video_device = data;
1616 struct acpi_device *device = NULL;
1617 struct acpi_video_bus *bus;
1618 struct input_dev *input;
1619 int keycode = 0;
1620
1621 if (!video_device)
1622 return;
1623
1624 device = video_device->dev;
1625 bus = video_device->video;
1626 input = bus->input;
1627
1628 switch (event) {
1629 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
1630 brightness_switch_event(video_device, event);
1631 keycode = KEY_BRIGHTNESS_CYCLE;
1632 break;
1633 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
1634 brightness_switch_event(video_device, event);
1635 keycode = KEY_BRIGHTNESSUP;
1636 break;
1637 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
1638 brightness_switch_event(video_device, event);
1639 keycode = KEY_BRIGHTNESSDOWN;
1640 break;
1641 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1642 brightness_switch_event(video_device, event);
1643 keycode = KEY_BRIGHTNESS_ZERO;
1644 break;
1645 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
1646 brightness_switch_event(video_device, event);
1647 keycode = KEY_DISPLAY_OFF;
1648 break;
1649 default:
1650 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1651 "Unsupported event [0x%x]\n", event));
1652 break;
1653 }
1654
1655 acpi_notifier_call_chain(device, event, 0);
1656
1657 if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1658 input_report_key(input, keycode, 1);
1659 input_sync(input);
1660 input_report_key(input, keycode, 0);
1661 input_sync(input);
1662 }
1663
1664 return;
1665}
1666
1667static int acpi_video_resume(struct notifier_block *nb,
1668 unsigned long val, void *ign)
1669{
1670 struct acpi_video_bus *video;
1671 struct acpi_video_device *video_device;
1672 int i;
1673
1674 switch (val) {
1675 case PM_HIBERNATION_PREPARE:
1676 case PM_SUSPEND_PREPARE:
1677 case PM_RESTORE_PREPARE:
1678 return NOTIFY_DONE;
1679 }
1680
1681 video = container_of(nb, struct acpi_video_bus, pm_nb);
1682
1683 dev_info(&video->device->dev, "Restoring backlight state\n");
1684
1685 for (i = 0; i < video->attached_count; i++) {
1686 video_device = video->attached_array[i].bind_info;
1687 if (video_device && video_device->brightness)
1688 acpi_video_device_lcd_set_level(video_device,
1689 video_device->brightness->curr);
1690 }
1691
1692 return NOTIFY_OK;
1693}
1694
1695static acpi_status
1696acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1697 void **return_value)
1698{
1699 struct acpi_device *device = context;
1700 struct acpi_device *sibling;
1701 int result;
1702
1703 if (handle == device->handle)
1704 return AE_CTRL_TERMINATE;
1705
1706 result = acpi_bus_get_device(handle, &sibling);
1707 if (result)
1708 return AE_OK;
1709
1710 if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1711 return AE_ALREADY_EXISTS;
1712
1713 return AE_OK;
1714}
1715
1716static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1717{
1718 struct backlight_properties props;
1719 struct pci_dev *pdev;
1720 acpi_handle acpi_parent;
1721 struct device *parent = NULL;
1722 int result;
1723 static int count;
1724 char *name;
1725
1726 result = acpi_video_init_brightness(device);
1727 if (result)
1728 return;
1729
1730 if (disable_backlight_sysfs_if > 0)
1731 return;
1732
1733 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1734 if (!name)
1735 return;
1736 count++;
1737
1738 acpi_get_parent(device->dev->handle, &acpi_parent);
1739
1740 pdev = acpi_get_pci_dev(acpi_parent);
1741 if (pdev) {
1742 parent = &pdev->dev;
1743 pci_dev_put(pdev);
1744 }
1745
1746 memset(&props, 0, sizeof(struct backlight_properties));
1747 props.type = BACKLIGHT_FIRMWARE;
1748 props.max_brightness =
1749 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1750 device->backlight = backlight_device_register(name,
1751 parent,
1752 device,
1753 &acpi_backlight_ops,
1754 &props);
1755 kfree(name);
1756 if (IS_ERR(device->backlight)) {
1757 device->backlight = NULL;
1758 return;
1759 }
1760
1761 /*
1762 * Save current brightness level in case we have to restore it
1763 * before acpi_video_device_lcd_set_level() is called next time.
1764 */
1765 device->backlight->props.brightness =
1766 acpi_video_get_brightness(device->backlight);
1767
1768 device->cooling_dev = thermal_cooling_device_register("LCD",
1769 device->dev, &video_cooling_ops);
1770 if (IS_ERR(device->cooling_dev)) {
1771 /*
1772 * Set cooling_dev to NULL so we don't crash trying to free it.
1773 * Also, why the hell we are returning early and not attempt to
1774 * register video output if cooling device registration failed?
1775 * -- dtor
1776 */
1777 device->cooling_dev = NULL;
1778 return;
1779 }
1780
1781 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1782 device->cooling_dev->id);
1783 result = sysfs_create_link(&device->dev->dev.kobj,
1784 &device->cooling_dev->device.kobj,
1785 "thermal_cooling");
1786 if (result)
1787 printk(KERN_ERR PREFIX "Create sysfs link\n");
1788 result = sysfs_create_link(&device->cooling_dev->device.kobj,
1789 &device->dev->dev.kobj, "device");
1790 if (result)
1791 printk(KERN_ERR PREFIX "Create sysfs link\n");
1792}
1793
1794static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1795{
1796 struct acpi_video_device *dev;
1797 union acpi_object *levels;
1798
1799 mutex_lock(&video->device_list_lock);
1800 list_for_each_entry(dev, &video->video_device_list, entry) {
1801 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1802 kfree(levels);
1803 }
1804 mutex_unlock(&video->device_list_lock);
1805}
1806
1807static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1808{
1809 /*
1810 * Do not create backlight device for video output
1811 * device that is not in the enumerated list.
1812 */
1813 if (!acpi_video_device_in_dod(dev)) {
1814 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1815 return false;
1816 }
1817
1818 if (only_lcd)
1819 return dev->flags.lcd;
1820 return true;
1821}
1822
1823static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1824{
1825 struct acpi_video_device *dev;
1826
1827 if (video->backlight_registered)
1828 return 0;
1829
1830 acpi_video_run_bcl_for_osi(video);
1831
1832 if (acpi_video_get_backlight_type() != acpi_backlight_video)
1833 return 0;
1834
1835 mutex_lock(&video->device_list_lock);
1836 list_for_each_entry(dev, &video->video_device_list, entry) {
1837 if (acpi_video_should_register_backlight(dev))
1838 acpi_video_dev_register_backlight(dev);
1839 }
1840 mutex_unlock(&video->device_list_lock);
1841
1842 video->backlight_registered = true;
1843
1844 video->pm_nb.notifier_call = acpi_video_resume;
1845 video->pm_nb.priority = 0;
1846 return register_pm_notifier(&video->pm_nb);
1847}
1848
1849static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1850{
1851 if (device->backlight) {
1852 backlight_device_unregister(device->backlight);
1853 device->backlight = NULL;
1854 }
1855 if (device->brightness) {
1856 kfree(device->brightness->levels);
1857 kfree(device->brightness);
1858 device->brightness = NULL;
1859 }
1860 if (device->cooling_dev) {
1861 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1862 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1863 thermal_cooling_device_unregister(device->cooling_dev);
1864 device->cooling_dev = NULL;
1865 }
1866}
1867
1868static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1869{
1870 struct acpi_video_device *dev;
1871 int error;
1872
1873 if (!video->backlight_registered)
1874 return 0;
1875
1876 error = unregister_pm_notifier(&video->pm_nb);
1877
1878 mutex_lock(&video->device_list_lock);
1879 list_for_each_entry(dev, &video->video_device_list, entry)
1880 acpi_video_dev_unregister_backlight(dev);
1881 mutex_unlock(&video->device_list_lock);
1882
1883 video->backlight_registered = false;
1884
1885 return error;
1886}
1887
1888static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1889{
1890 acpi_status status;
1891 struct acpi_device *adev = device->dev;
1892
1893 status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1894 acpi_video_device_notify, device);
1895 if (ACPI_FAILURE(status))
1896 dev_err(&adev->dev, "Error installing notify handler\n");
1897 else
1898 device->flags.notify = 1;
1899}
1900
1901static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1902{
1903 struct input_dev *input;
1904 struct acpi_video_device *dev;
1905 int error;
1906
1907 video->input = input = input_allocate_device();
1908 if (!input) {
1909 error = -ENOMEM;
1910 goto out;
1911 }
1912
1913 error = acpi_video_bus_start_devices(video);
1914 if (error)
1915 goto err_free_input;
1916
1917 snprintf(video->phys, sizeof(video->phys),
1918 "%s/video/input0", acpi_device_hid(video->device));
1919
1920 input->name = acpi_device_name(video->device);
1921 input->phys = video->phys;
1922 input->id.bustype = BUS_HOST;
1923 input->id.product = 0x06;
1924 input->dev.parent = &video->device->dev;
1925 input->evbit[0] = BIT(EV_KEY);
1926 set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1927 set_bit(KEY_VIDEO_NEXT, input->keybit);
1928 set_bit(KEY_VIDEO_PREV, input->keybit);
1929 set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1930 set_bit(KEY_BRIGHTNESSUP, input->keybit);
1931 set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1932 set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1933 set_bit(KEY_DISPLAY_OFF, input->keybit);
1934
1935 error = input_register_device(input);
1936 if (error)
1937 goto err_stop_dev;
1938
1939 mutex_lock(&video->device_list_lock);
1940 list_for_each_entry(dev, &video->video_device_list, entry)
1941 acpi_video_dev_add_notify_handler(dev);
1942 mutex_unlock(&video->device_list_lock);
1943
1944 return 0;
1945
1946err_stop_dev:
1947 acpi_video_bus_stop_devices(video);
1948err_free_input:
1949 input_free_device(input);
1950 video->input = NULL;
1951out:
1952 return error;
1953}
1954
1955static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1956{
1957 if (dev->flags.notify) {
1958 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1959 acpi_video_device_notify);
1960 dev->flags.notify = 0;
1961 }
1962}
1963
1964static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1965{
1966 struct acpi_video_device *dev;
1967
1968 mutex_lock(&video->device_list_lock);
1969 list_for_each_entry(dev, &video->video_device_list, entry)
1970 acpi_video_dev_remove_notify_handler(dev);
1971 mutex_unlock(&video->device_list_lock);
1972
1973 acpi_video_bus_stop_devices(video);
1974 input_unregister_device(video->input);
1975 video->input = NULL;
1976}
1977
1978static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1979{
1980 struct acpi_video_device *dev, *next;
1981
1982 mutex_lock(&video->device_list_lock);
1983 list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1984 list_del(&dev->entry);
1985 kfree(dev);
1986 }
1987 mutex_unlock(&video->device_list_lock);
1988
1989 return 0;
1990}
1991
1992static int instance;
1993
1994static int acpi_video_bus_add(struct acpi_device *device)
1995{
1996 struct acpi_video_bus *video;
1997 int error;
1998 acpi_status status;
1999
2000 status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2001 device->parent->handle, 1,
2002 acpi_video_bus_match, NULL,
2003 device, NULL);
2004 if (status == AE_ALREADY_EXISTS) {
2005 printk(KERN_WARNING FW_BUG
2006 "Duplicate ACPI video bus devices for the"
2007 " same VGA controller, please try module "
2008 "parameter \"video.allow_duplicates=1\""
2009 "if the current driver doesn't work.\n");
2010 if (!allow_duplicates)
2011 return -ENODEV;
2012 }
2013
2014 video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2015 if (!video)
2016 return -ENOMEM;
2017
2018 /* a hack to fix the duplicate name "VID" problem on T61 */
2019 if (!strcmp(device->pnp.bus_id, "VID")) {
2020 if (instance)
2021 device->pnp.bus_id[3] = '0' + instance;
2022 instance++;
2023 }
2024 /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2025 if (!strcmp(device->pnp.bus_id, "VGA")) {
2026 if (instance)
2027 device->pnp.bus_id[3] = '0' + instance;
2028 instance++;
2029 }
2030
2031 video->device = device;
2032 strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2033 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2034 device->driver_data = video;
2035
2036 acpi_video_bus_find_cap(video);
2037 error = acpi_video_bus_check(video);
2038 if (error)
2039 goto err_free_video;
2040
2041 mutex_init(&video->device_list_lock);
2042 INIT_LIST_HEAD(&video->video_device_list);
2043
2044 error = acpi_video_bus_get_devices(video, device);
2045 if (error)
2046 goto err_put_video;
2047
2048 printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s rom: %s post: %s)\n",
2049 ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2050 video->flags.multihead ? "yes" : "no",
2051 video->flags.rom ? "yes" : "no",
2052 video->flags.post ? "yes" : "no");
2053 mutex_lock(&video_list_lock);
2054 list_add_tail(&video->entry, &video_bus_head);
2055 mutex_unlock(&video_list_lock);
2056
2057 acpi_video_bus_register_backlight(video);
2058 acpi_video_bus_add_notify_handler(video);
2059
2060 return 0;
2061
2062err_put_video:
2063 acpi_video_bus_put_devices(video);
2064 kfree(video->attached_array);
2065err_free_video:
2066 kfree(video);
2067 device->driver_data = NULL;
2068
2069 return error;
2070}
2071
2072static int acpi_video_bus_remove(struct acpi_device *device)
2073{
2074 struct acpi_video_bus *video = NULL;
2075
2076
2077 if (!device || !acpi_driver_data(device))
2078 return -EINVAL;
2079
2080 video = acpi_driver_data(device);
2081
2082 acpi_video_bus_remove_notify_handler(video);
2083 acpi_video_bus_unregister_backlight(video);
2084 acpi_video_bus_put_devices(video);
2085
2086 mutex_lock(&video_list_lock);
2087 list_del(&video->entry);
2088 mutex_unlock(&video_list_lock);
2089
2090 kfree(video->attached_array);
2091 kfree(video);
2092
2093 return 0;
2094}
2095
2096static int __init is_i740(struct pci_dev *dev)
2097{
2098 if (dev->device == 0x00D1)
2099 return 1;
2100 if (dev->device == 0x7000)
2101 return 1;
2102 return 0;
2103}
2104
2105static int __init intel_opregion_present(void)
2106{
2107 int opregion = 0;
2108 struct pci_dev *dev = NULL;
2109 u32 address;
2110
2111 for_each_pci_dev(dev) {
2112 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2113 continue;
2114 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2115 continue;
2116 /* We don't want to poke around undefined i740 registers */
2117 if (is_i740(dev))
2118 continue;
2119 pci_read_config_dword(dev, 0xfc, &address);
2120 if (!address)
2121 continue;
2122 opregion = 1;
2123 }
2124 return opregion;
2125}
2126
2127/* Check if the chassis-type indicates there is no builtin LCD panel */
2128static bool dmi_is_desktop(void)
2129{
2130 const char *chassis_type;
2131 unsigned long type;
2132
2133 chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2134 if (!chassis_type)
2135 return false;
2136
2137 if (kstrtoul(chassis_type, 10, &type) != 0)
2138 return false;
2139
2140 switch (type) {
2141 case 0x03: /* Desktop */
2142 case 0x04: /* Low Profile Desktop */
2143 case 0x05: /* Pizza Box */
2144 case 0x06: /* Mini Tower */
2145 case 0x07: /* Tower */
2146 case 0x10: /* Lunch Box */
2147 case 0x11: /* Main Server Chassis */
2148 return true;
2149 }
2150
2151 return false;
2152}
2153
2154int acpi_video_register(void)
2155{
2156 int ret = 0;
2157
2158 mutex_lock(&register_count_mutex);
2159 if (register_count) {
2160 /*
2161 * if the function of acpi_video_register is already called,
2162 * don't register the acpi_vide_bus again and return no error.
2163 */
2164 goto leave;
2165 }
2166
2167 /*
2168 * We're seeing a lot of bogus backlight interfaces on newer machines
2169 * without a LCD such as desktops, servers and HDMI sticks. Checking
2170 * the lcd flag fixes this, so enable this on any machines which are
2171 * win8 ready (where we also prefer the native backlight driver, so
2172 * normally the acpi_video code should not register there anyways).
2173 */
2174 if (only_lcd == -1) {
2175 if (dmi_is_desktop() && acpi_osi_is_win8())
2176 only_lcd = true;
2177 else
2178 only_lcd = false;
2179 }
2180
2181 dmi_check_system(video_dmi_table);
2182
2183 ret = acpi_bus_register_driver(&acpi_video_bus);
2184 if (ret)
2185 goto leave;
2186
2187 /*
2188 * When the acpi_video_bus is loaded successfully, increase
2189 * the counter reference.
2190 */
2191 register_count = 1;
2192
2193leave:
2194 mutex_unlock(&register_count_mutex);
2195 return ret;
2196}
2197EXPORT_SYMBOL(acpi_video_register);
2198
2199void acpi_video_unregister(void)
2200{
2201 mutex_lock(&register_count_mutex);
2202 if (register_count) {
2203 acpi_bus_unregister_driver(&acpi_video_bus);
2204 register_count = 0;
2205 }
2206 mutex_unlock(&register_count_mutex);
2207}
2208EXPORT_SYMBOL(acpi_video_unregister);
2209
2210void acpi_video_unregister_backlight(void)
2211{
2212 struct acpi_video_bus *video;
2213
2214 mutex_lock(&register_count_mutex);
2215 if (register_count) {
2216 mutex_lock(&video_list_lock);
2217 list_for_each_entry(video, &video_bus_head, entry)
2218 acpi_video_bus_unregister_backlight(video);
2219 mutex_unlock(&video_list_lock);
2220 }
2221 mutex_unlock(&register_count_mutex);
2222}
2223
2224bool acpi_video_handles_brightness_key_presses(void)
2225{
2226 bool have_video_busses;
2227
2228 mutex_lock(&video_list_lock);
2229 have_video_busses = !list_empty(&video_bus_head);
2230 mutex_unlock(&video_list_lock);
2231
2232 return have_video_busses &&
2233 (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2234}
2235EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2236
2237/*
2238 * This is kind of nasty. Hardware using Intel chipsets may require
2239 * the video opregion code to be run first in order to initialise
2240 * state before any ACPI video calls are made. To handle this we defer
2241 * registration of the video class until the opregion code has run.
2242 */
2243
2244static int __init acpi_video_init(void)
2245{
2246 /*
2247 * Let the module load even if ACPI is disabled (e.g. due to
2248 * a broken BIOS) so that i915.ko can still be loaded on such
2249 * old systems without an AcpiOpRegion.
2250 *
2251 * acpi_video_register() will report -ENODEV later as well due
2252 * to acpi_disabled when i915.ko tries to register itself afterwards.
2253 */
2254 if (acpi_disabled)
2255 return 0;
2256
2257 if (intel_opregion_present())
2258 return 0;
2259
2260 return acpi_video_register();
2261}
2262
2263static void __exit acpi_video_exit(void)
2264{
2265 acpi_video_detect_exit();
2266 acpi_video_unregister();
2267
2268 return;
2269}
2270
2271module_init(acpi_video_init);
2272module_exit(acpi_video_exit);
2273